Strobe tuner

Abstract

Single and multiple disc strobe tuners employ microprocessor controlled stepper motors for driving the disc(s) to facilitate the use of customized tuning schemes, such as unequal temperaments and stretch tuning. The tuning schemes are stored in a look up table and may be programmed by the user. The single disc embodiment preferably employs an auto note detector which determines the identity of a note being played by an instrument, and causes the microprocessor to adjust the speed of the stepper motor almost instantaneously to a speed assigned to that note in accordance with a selected tuning scheme. This enables a user to play through a series of notes rapidly to verify whether they are in tune with the selected tuning scheme. The multiple, preferably 12, disc embodiment employs a separate stepper motor and micro controller for each disc to accommodate individual tuning of each disc relative to one another. A main microprocessor is employed in this embodiment to control each of the micro controllers, and a master oscillator supplies clock pulses to all of the circuit elements to maintain synchronism with one another.

What is claimed is: 
     
       1. A strobe tuner for use in tuning a musical instrument comprising: a) a strobe disc having a strobe pattern disposed thereon;   b) a motor connected to said disc for rotating said disc;   c) microprocessor means for controlling the speed of said motor;   d) memory means interfaced to said microprocessor means for storing tuning data for each of a plurality of musical notes, said data to be used by said microprocessor means for controlling the speed of said motor;   e) a light source for illuminating said strobe pattern as said strobe disc rotates;   f) means for detecting a sound played by a musical instrument and flashing said light source at a frequency proportional to an audio frequency of said sound; and   g) input means interfaced to said microprocessor means for entering tuning data for a plurality of notes to which an instrument is to be tuned into said microprocessor means.   
     
     
       2. The strobe tuner of claim 1, wherein said motor is a digital stepper motor, and said microprocessor means includes means for supplying digital position data to said stepper motor in response to said tuning data for causing said strobe disc to be rotated at a speed at which said strobe pattern appears to be stopped by the flashing of said light source when a sound is detected having the same pitch as a note corresponding to said tuning data. 
     
     
       3. The strobe tuner of claim 2, further including means for determining the identity of a detected musical note corresponding to a detected sound, and means in said microprocessor responsive to said determined identity for causing said motor to rotate at a speed assigned to said detected note. 
     
     
       4. The strobe tuner of claim 1, wherein said input means includes note selection means and vernier pitch offset selection means for entering tuning data for a selected note. 
     
     
       5. The strobe tuner of claim 4, wherein said input means further includes key selection means for selecting a musical key to which said strobe tuner is tuned. 
     
     
       6. The strobe tuner of claim 5, wherein said input means further includes means for adjusting a frequency assigned to the middle A note of a selected key. 
     
     
       7. The strobe tuner of claim 1, further including: h) a second strobe disc having a strobe pattern disposed thereon;   i) a second motor connected to said second strobe disc for rotating said disc; and   j) means in said microprocessor means for rotating said first motor at a speed assigned to a first musical note stored in said memory means, and means for rotating said second motor at a speed assigned to a second musical note stored in said memory means.   
     
     
       8. The strobe tuner of claim 7, wherein said microprocessor means includes: 1) a first micro controller for controlling said first motor;   2) a second micro controller for controlling said second motor; and   3) a main microprocessor for sending motor position control signals to said first and second micro controllers.   
     
     
       9. The strobe tuner of claim 8, further including an oscillator means for generating clock pulses for controlling operation of said first and second microcontrollers, and said main microprocessor. 
     
     
       10. The strobe tuner of claim 1, wherein said means for detecting a sound further includes a low pass filter for selectively removing higher order harmonics from a detected sound. 
     
     
       11. The strobe tuner of claim 1, wherein said means for detecting a sound and flashing said light source further includes means for adjusting the intensity of said light source. 
     
     
       12. The strobe tuner of claim 1, further including means for cycling said microprocessor means through a sequence of pitch data for a plurality of notes, and causing said motor to rotate said strobe disc at a speed assigned to each of said plurality of notes. 
     
     
       13. A strobe tuner for use in tuning a musical instrument comprising: a) a plurality of strobe discs, each having a strobe pattern disposed thereon;   b) a plurality of digital stepper motors, each connected to a corresponding one of said strobe discs for rotating the same;   c) a plurality of microcontrollers, each for supplying position control signals to a corresponding one of said stepper motors;   d) a main microprocessor means for supplying motor position data to each of said microcontrollers;   e) memory means interfaced to said microprocessor means for storing tuning data for each of a plurality of musical notes to be used by said microprocessor means for supplying motor position data to each of said microcontrollers;   f) a light source for illuminating said strobe patterns as said strobe discs rotate;   g) means for detecting a sound played by a musical instrument and flashing said light source at a frequency proportional to an audio frequency of said sound; and   h) input means interfaced to said microprocessor means for entering tuning data for a plurality of notes into said microprocessor means.   
     
     
       14. The strobe tuner of claim 13, further comprising an oscillator means for generating clock pulses for controlling operation of said main microprocessor means and each of said microcontrollers. 
     
     
       15. The strobe tuner of claim 13, wherein 12 of each of said strobe discs, stepper motors and microcontrollers are provided, each of which is assigned to one of 12 musical notes in an octave. 
     
     
       16. A method for determining the tuning of a musical instrument comprising the steps of: a) providing at least one strobe disc having a strobe pattern disposed thereon and a motor connected to said disc for rotating the same;   b) providing a microprocessor means for controlling the speed of said motor;   c) storing tuning data for each of a plurality of musical notes in a memory means interfaced to said microprocessor means;   d) employing said tuning data to supply speed control signals to said motor for rotating said strobe disc at a speed assigned to a selected musical note;   e) providing a light source for illuminating said strobe pattern as said strobe disc rotates;   f) detecting a sound played by a musical instrument; and   g) flashing said light source at a frequency proportional to an audio frequency of said sound;   whereby, said strobe pattern is appeared to be stopped by the flashing of said light source if said detected sound is in tune with said selected musical note.   
     
     
       17. The method of claim 16, wherein the steps of providing a strobe disc and providing a microprocessor means further comprise: 1) providing a plurality of strobe discs, each having a strobe pattern disposed thereon and each having a digital stepper motor connected to said disc for rotating the same;   2) providing a plurality of microcontrollers, each for supplying position control data to a corresponding one of said digital stepper motors for controlling the speed of the same; and   3) providing a main microprocessor for supplying motor position data to each of said microcontrollers.   
     
     
       18. The method of claim 17, further comprising the step of providing an oscillator means for supplying clock pulses to each of said microcontrollers and to said main microprocessor. 
     
     
       19. The method of claim 16, further comprising the steps of detecting the identity of a musical note played by a musical instrument, and, in response to said identity detecting, causing said strobe disc to be rotated at a speed assigned to said detected musical note. 
     
     
       20. The method of claim 19, wherein said step of providing a strobe disc and a motor connected to said disc further comprises providing a digital stepper motor connected to said disc for rotating the same.